The Beneficial Effect of Exercise on the Cardiovascular SystemEssay Preview: The Beneficial Effect of Exercise on the Cardiovascular SystemReport this essayincreased risk of injury and overtraining.[citation needed]Both aerobic and anaerobic exercise work to increase the mechanical efficiency of the heart by increasing cardiac volume (aerobic exercise), or myocardial thickness (strength training). Such changes are generally beneficial and healthy if they occur in response to exercise.
Not everyone benefits equally from exercise. There is tremendous variation in individual response to training; where most people will see a moderate increase in endurance from aerobic exercise, some individuals will as much as double their oxygen uptake, while others can never augment endurance.[20][21] However, muscle hypertrophy from resistance training is primarily determined by diet and testosterone.[22] This genetic variation in improvement from training is one of the key physiological differences between elite athletes and the larger population.[23][24] Studies have shown that exercising in middle age leads to better physical ability later in life.[25]
[edit]Effect on the cardiovascular systemThe beneficial effect of exercise on the cardiovascular system is well documented.There is a direct relation between physical inactivity and cardiovascular mortality, and physical inactivity is an independent risk factor for the development of coronary artery disease. There is a dose-response relation between the amount of exercise performed from approximately 700 to 2000 kcal of energy expenditure per week and all-cause mortality and cardiovascular disease mortality in middle-aged and elderly populations. The greatest potential for reduced mortality is in the sedentary who become moderately active. Most beneficial effects of physical activity on cardiovascular disease mortality can be attained through moderate-intensity activity (40% to 60% of maximal oxygen uptake, depending on age). persons who modify their behavior after myocardial infarction to include regular exercise have improved rates of survival. Persons who remain sedentary have the highest risk for all-cause and cardiovascular disease mortality.[26]
[edit]Effect on the immune systemAlthough there have been hundreds of studies on exercise and the immune system, there is little direct evidence on its connection to illness. Epidemiological evidence suggests that moderate exercise has a beneficial effect on the human immune system; an effect which is modeled in a J curve. Moderate exercise has been associated with a 29% decreased incidence of upper respiratory tract infections (URTI), but studies of marathon runners found that their prolonged high-intensity exercise was associated with an increased risk of infection occurrence. However, another study did not find the effect. Immune cell functions are impaired following acute sessions of prolonged, high-intensity exercise, and some studies
[edit]On balance, exercise has been shown to have a greater effect on the immune system than conventional medical treatments. One observational study has shown that exercise improves the serum T, which is important in combating immunodeficiency; another randomized trial found that heavy exercise was not associated with increased C-reactive protein levels in rats or that exercise was associated with increased immunity to viral infections. Exercise has also significantly increased lymphocyte count, which is associated with a lower risk of death in an animal model of lymphoma, and increases mortality in mice, according to the University of Minnesota Medical Center’s (UMNMD) “Risk-Taking Effect” study.
[edit]The results of this post have been mixed, so I’ve decided to leave out all the experimental data and see if there’s a connection with the research we’ve already discussed.
It does seem that when compared to the general population, exercise (along with water, coffee, and other foods) has been found to decrease body weight.
[edit]A recent review of evidence on exercise has also addressed these two questions. Some articles have suggested that exercise leads to short-term weight loss or that exercise may help the body adapt to stressors (Mann-Whitney Tests) to the degree likely observed during exercise. Also, some reports show that exercise actually increases insulin sensitivity through its effect on the hypothalamic–pituitary–adrenal axis, which supports the hypothesis that exercise might improve the hormonal response to stressful life events (Mann-Whitney Tests). (However, some studies report only mildly elevations in cortisol and ghrelin levels and that exercise might also help to prevent post-traumatic stress disorder and other major stressors.) In addition, some reports suggest that exercise can reduce the risk of breast cancer risk. (We will discuss these findings in more detail in this post.) While there are a few things that remain unproven, there is a clear link between exercise and cancer mortality, especially high-risk breast cancer events.
[edit]Another factor that was noted in previous studies that seems to be driving the increased mortality was a combination of factors, some of which I’ve mentioned above.
[edit]On summary, in my opinion, the only information I’ve seen or seen from scientific evidence that will stand apart from my own research is that there’s currently no reason to believe that exercise increases cancer risk. There are very few studies which show a significant increase in cancer incidence, or cancer mortality, but there is absolutely ample evidence that exercise causes significant declines in certain cancers.
[edit]In my opinion, the biggest evidence of an increase in cancer mortality lies in studies of exercise, and even in studies that are not self-conducted. Studies with subjects often have to be conducted with very high risk variables in this context (for example, subjects who are overweight, underweight, or obese for other reasons), and this can require training.
This is where you end up with an issue where there are